1. Field
Example embodiments generally relate to an image forming apparatus such as printers, copying machines, facsimiles, etc. capable of forming an visible image on an image bearer such as photoconductor drums, for example.
2. Discussion of the Background
Background image forming apparatuses may typically form a nip between an image bearer and a transfer belt and/or a charge roller. Such image forming apparatus may cause a problem in that the image bearer is rubbed due to the difference in moving speed between the image bearer and the contacting member (i.e., the transfer belt and charging roller) especially when the image bearer stops of rotation, resulting deterioration of the image bearer. The above-mentioned moving speed difference may generally become large just before stop of rotation of the image bearer. Therefore, stopping of the image bearer at the same stop position may accelerate deterioration of the image bearer because the same portion of the surface of the image bearer may be worn in every stop operation of the image bearer.
In attempting to solve this problem, a background image forming apparatus changing the stop position in every driving stop operation of the image bearer is proposed. Specifically, the stop position, i.e., the nip between a photoconductor endless belt serving as an image bearer and a contacting member may be controlled. In this example, acceleration of deterioration of the photoconductor endless belt caused by wearing at every stop operation of may be controlled.
However, if the stop position of an image bearer is changed by 10 degrees, for example, the image bearer may be stopped at the same position after every 36 (360/10) stop operations. This stop operation may also accelerate the deterioration of the image bearer. Further, the same portion of the image bearer may receive a maximum pressure after every 36 stop operations. Then, a wear strongly may occur in the same portion of the maximum pressure in the nip, being worn repeatedly every rotation.
This problem may occur on not only a cylindrical photoconductor drum but also an endless photoconductor belt as an image bearer.